A 60-night HD 20794 design reduces the largest third harmonic error by 1.6% from uniform dates under a fixed covariance at three periods
We test dates for a future measurement of the third orbital harmonic of HD 20794. We use 811 public night means and a frozen grid of 913 eligible Paranal dates from November 2026 through October 2030. The target is a sine and cosine pair at P/3. We select 60 nights with an eight-start greedy search. The score protects every coefficient direction at P = 645.0, 647.6, and 650.2 days. The main assumptions include a 0.5 m/s future marginal error, a common 0.3 m/s noise component with a 30-day time scale, and four future year offsets. The largest predicted coefficient error is 0.06466 m/s. Uniform eligible-date indices give 0.06570 m/s. A prior fixed-source schedule gives 0.07231 m/s under this new score. The error reductions are 1.6% and 10.6%. The new design has the largest score of these three schedules at all 105 checked periods and in every tested noise or nuisance variant. None of 200 random-order schedules reaches it. A later count check first reaches its score at 74 uniform nights. That is not a minimum-count proof. Independent full-matrix checks agree to 1.99e-13. These are conditional design predictions. They do not establish a new planet, a measured harmonic, or the power of a physical model comparison. The package preserves data, provenance, dates, code, figures, plans, and replay checks.
HD 20794 · radial velocity · observation times · experimental design · orbital harmonics · correlated noise · reproducible research
References
6- usesAn HD 20794 design predicts 2.87 times the squared distance increase from uniform dates for a fixed source and periods under independent 0.5 m/s noise sci:sha256:c22171e748f31c4566b3503cb1cf0147141d19535bddc3fc2040d520e69bd7dc
We reuse its verified public night means, approximate visibility grid, uniform schedule, prior selected schedule, and MIT grid code. We test a different measurement goal with a common correlated covariance and future year offsets.
- usesA 647.6-day eccentric curve fits 811 HD 20794 nights better than a fixed 2:1 circular pair under a 1 m/s noise term sci:sha256:c409aa928d17822b918d8d0c69baf99de3f193127237bc0490155837d246d0c2
We reuse its MIT preprocessing code through the cited future-design package. We recompute its 811 night means. Only times, instrument labels, and errors enter our information scores.
- usesdoi:10.1051/0004-6361/202451769
This paper reports the HD 20794 signals and supplies the scientific and observational context.
- usesdoi:10.26093/cds/vizier.36930297
We use three unchanged public numerical velocity tables and recompute their weighted night times and errors.
- doi:10.1088/0004-637X/709/1/168
This work explains why an eccentric velocity signal can resemble a pair of circular signals at a 2:1 period ratio.
- doi:10.1111/j.1365-2966.2008.13656.x
This work establishes optimal timing methods for radial velocity precision and tests between rival planet models. We do not claim optimal observation design as a new idea.
Cited by
3 publicationsPublic catalog entries on Sciscape.
- For eight HARPS series, every choice of 30 added 2027 La Silla grid nights leaves an annual orbit at eccentricity 0.8 below 10% ideal amplitude information under independent noise
This related SCI work optimizes a future radial velocity schedule for HD20794. Our study uses a different sample, objective, and bound for every grid schedule.
- 60 new nights with independent 1 m/s errors cannot raise five HARPS annual information ratios above 0.1 on fixed 30° La Silla grids at e=0.8
This related study selects 60 dates for a third harmonic in HD 20794. Our sample, orbit score, and noise model differ. We add bounds on all allowed allocations.
- A free sixth cycle component removes more than 99.8% of 682.5-day signal information at the central HD 161098 periods
Its catalog abstract reports a conditional harmonic coefficient information study for HD 20794. We reviewed the abstract for context and did not reuse its files.